Outlet for humidifying ducts



May 3, 1949.

A. H. BAHNSON, JR l OUTLET FOR HUMIDIFYING DUCTS Filed Aug. 9, 1944 Patented May 3, 1949 UNIT ED S TAT E erm OFFICE 9 Claims. 1

This invention relates to outlets for humidifying ducts and more particularly to outlets forI a Wet duct humidifier system.

In these syst'ems'at least one blower or fan is employed to' draw air into a distributing duct and to blow it under pressure through said duct. At'r least one humidifying device or atomizer is located in the duct, usually adjacent the discharge sideof the blower. The compressed and humidied air iiows along the duct, which leads through the space*v to be humidied, and is discharged therefrom at spaced points by means of outletsv or discharge nozzles. A Wet duct system of this type isydescribed. more completely in my Patent No. 2,358,847; The present application in some respectsl constitutes a continuation-in-part of thisacknowledged prior application.

Itis essential that all water discharged from the duct be either fully vaporized or in the form of a mist whose particles are so fine that they evaporate quicklyin the room air before reachingmachinery or goods that might be damaged` by water.. One condition that may result in damagev from water is the tendency: of lint to collect inr sltreamers at the discharge ends of the outlets and. for Water to,- follow along the stre'arnersl and to be blown in drops from. their outer ends. It is also true that, if the outlets do not make a tight jointv where they Contact the duct, wet air may be'bl'own out at this point which frequently carries water in the form of drops. 'Ihe discharge of water at any point in the form of drops is, of course,` highly objectionable as it may'cause considerable damage tothe machinery or the materials in the room.

The practice has been to solder flanged outlets to the outer wall of the duct to prevent the escape of Water drops but I have found that a much simpler and less expensive joint construction will aiiord adequate protection against the blowing Iof water drops into the room air. Water tending to escape through thel joint will be blown along the tapered outlet, and evaporated before it reaches the end ofthe outlet, when the outlet flange is positioned within the duct and drawn into reasonably tight engagement with the inner surface of the duct by a seriesv of bendable strips that are riveted to the outlet.

Objects ofthe present invention are to provide duct outlets of simple and inexpensive construction thatmay be detachably secured in place on a humidifier or air conditioning duct. An object is to provide awet duct outlet having annu-ter endconstruction that precludes the formation of lint streamer's. A further object is to provide duct outlets with attached collars at their outlet ends, the collars being shaped to preclude the formation of lint streamers and, preferably, of a standard or uniform size for outlets of' different lengths or of different inner end diameters.

These and other objects and advantages of' the invention will be apparent from the following; specification when taken with the accompanying drawing in which:

Fig. 1 is a fragmentary plan view of a Wet duct humidifier sytem having outlets. embodying the invention;

Fig. 2 is a perspective View of a flanged outlet collar;

Fig. 3 is a perspective view of an outletrshow'ingthe collar in position thereon;

Fig. 4 is a fragmentary vertical section throughy an outlet and adjacent ductv structure as seen on the plane indicated by line 4-4 of Fig. I;

Fig 5 is an enlarged section through the lip of an outlet showing diagrammatically the flow of the lint in the outlet; and

Fig. 6 is a similar enlarged sectional View of a modiiied outlet lip construction.

In the drawing, the reference numeral IA identifiesy the duct that is supported on an' outer wallf 2 of the room or mill and has a plurality of outlets 3 for discharging moist air and entrained Water mist into the room air. A blower fan 4i on shaft 5 centered in the duct is driven by a. belt 6 and motor 1 mounted outside the du'ct, the shaft 5 being journaled in suitable bearings 8 mounted in a frame 9. The fan draws outside air into inlet end Ill of the duct and means, not shown, may be provided for the recirculation of rooml air in admixture with or in place ofthey outside air. The air stream passes throughthe radial Vanes llwhich eliminate the radial component of motion imparted by the fan and then past a humidifying unit l2 that is centrally mounted in the ductby a bracket I3. The-humidifier unit may be of the atomizer typeor, as illustrated, of the type including a water' throwing disk I4 within a casing l5 and mountedl on a shaft lr6 which carries a. pulley I1 driveny by the motor 1 through the belt I8 Water fed to the disk i4 is projected against a vringof atomizer teeth, not shown, and converted' intof a ine mist which is entrained in andi evaporated by the air stream. The outlets 3 are spacedl along the length of the duct at suitable 'pointsto discharge the moisture laden air and' entrained waterwmist into the room.

The. outlets 3 comprise afsleeve portion-'19inthe shape of a truncated coney that has' an 'annular fiange 20 at its rear or inlet end, see Figs. 3 and 4. The outlet is mounted in the air duct by drawing its rear ange against the inner wall of the air duct I by straps or clips 2| that are secured to the inner wall of the outlets by rivets 22. Air and water mist that escapes through this joint is projected along the outlet sleeve i9 and no drops of water are blown into the room by the air that escapes through the joints.

The outlet 3 may be a unitary structure, as described hereinafter with reference to Fig. 6, but it is preferable to form the discharge end of the outlet as a detachable split collar 23 having an inner conical flange 24 snugly fitting within the outer end of the outlet sleeve i9. The collar 23 may be rolled or pressed from strip material and, as formed, is of somewhat larger diameter than will fit within the outlet, see Fig. 2. The collar is compressed or collapsed to introduce the flange 24 into the end of sleeve I9, and then allowed to expand into engagement with the sleeve. One edge of the outer iiared flange 25 of the collar is extended circumferentially beyond the radial split to provide a locking strip 26 that is bent over the other edge of flange 25 to loci; the collar in expanded position within the outlet sleeve, see Figs. 3 and 4.

The axes of the conical sleeves I9 of 'the outlets 3 are inclined or pitched towards the blower end of the duct to effect a smooth non-turbulent defiection of portions of the main duct air stream through the outlet and into the room along paths substantially normal to the duct axis. rIhe inner flange 24 of the collar is shaped to conform closely to the inner wall of sleeve it and therefore has a pitched circumferential portion 2l that merges into a straight or right cylindrical portion 28 at the opposite side of the flange, see Fig. 2.

The collar 23 or discharge end of the outlet is provided with internal circumferential ribs 29, 30 that are axially spaced to leave a circumferential groove 3l in which the air stream sets up an eddy or low velocity region in which lint may collect. The air stream is directed radially inwardly by the approach side of the circumferential rib 2t, and water particles, lint and other foreign material that may be entrained in the main body of the air stream are thereby directed away from the flared flange 25 that forms the outer end of the duct outlet. A vent or drain opening 32 is provided at the lower portion of the groove 3i for the escape of water that may collect in the groove. Water escaping through opening 32 is not discharged into the room but is caught by a trough, not shown, that is arranged below the duct and its outlets to carry away condensate or other water that may drip from the duct.

There is an aspiration of room air and formation of an annular eddy current at the concave face of the flaring flange 25 and, with heavy concentrations of lint in the room air, there may be some tendency for lint to deposit from this aspirated air upon the flange 25. This can be eliminated by forming the flaring flange in two sections, see Fig. 6, the inner section 25a being inclined at about 45 and the outer section 25o being inclined at about 65 to 70. The Fig. 6 embodiment differs in other respects from the construction illustrated in Figs. 1 to 5 as only a single circumferential rib 29 is used and this rib and the flaring flange 25a, 25h are integral with the outlet sleeve I9'. The single rib 29' is suiiicient, whether integral with the sleeve I9 or on an attached collar, to prevent the formation of streamers on the aring flange of the outlet when the amount of lint in the room air is relatively low.

While I have described what I consider to be the most advantageous embodiments of the invention, it is evident, of course, that various modications can be made in the structures which have been described without departing from the purview of this invention. Some features of outlet constructions make them advantageous for use in dry duct distribution systems as well as in the wet duct system which has been described. rlhe angle made by the flaring flange at the discharge end of the outlet can be varied rather widely. Various arrangements other than those described may be employed for securing the outlets to the air ducts and, of course, the collars can be mounted at the discharge ends of the outlets in other manners. These and other modifications of the invention which fall within the scope of the following claims will be recognized by those skilled in this art.

I claim:

1. An outlet of the type described which comprises a sleeve having the general shape of a truncated cone having one substantially straight side and an opposite side tapered towards the outlet, a flaring flange at the inlet end of said sleeve and a collar mounted at the discharge end of said sleeve, said collar having an outwardly flaring iiange and an inwardly extending annular rib circling the outlet adjacent said ange and forming the most constricted point of said outlet.

2. An outlet as recited in claim l wherein the said tapered side makes an angle of from about 15 to 25 with the axis of said sleeve.

3. An outlet as recited in claim 1 wherein the outwardly aring flange on said collar makes an angle of from about 50 to 90 with the axis of the outlet.

4. An outlet as recited in ciaim 1 wherein a second inwardly extending annular rib is provided at an axially spaced short distance to the rear of said first rib, leaving a channel therebetween.

5. An outlet as recited in claim 1 wherein said outwardly flaring flange comprises two sections at different inclinations to the axis of the outlet.

6. An outlet for the discharge of air from a humidifying duct, said outlet comprising an unobstructed tapered sleeve adapted to be secured at its larger end in an opening in the wall of the duct, a split collar detachably secured to the smaller end of said sleeve, said collar comprising a rearwardly and outwardly flaring ange tting the inner surface of said sleeve at the smaller end thereof and a forwardly and outwardly ilaring flange extending forwardly from the smaller end of said sleeve.

'7. An outlet for the discharge of air from a humidifying duct, said outlet comprising a sleeve mounted in an opening in the side wall of said duct and extending laterally therefrom, said sleeve having a relatively long internally unobstructed body portion which is tapered toward the discharge end thereof, a relatively short flange extending forwardly and outwardly from adjacent the discharge end of said body portion and an annular rib extending inwardly beyond the edge of the discharge end of said body portion and forming the most constructed point of the outlet connecting the discharge end of said body portion with said flange.

8. An outlet for the dicharge of air from a humidifying duct, said outlet comprising a sleeve mounted in an opening in the side wall of said duct and extending laterally therefrom, said sleeve having a relatively long internally unobstructed body portion which is tapered toward the discharge end thereof, a relatively short flange extending forwardly and outwardly from adjacent the discharge end of said body portion and two inwardly extending annular ribs and an intermediate outwardly extending annular rib connecting the discharge end of said body portion with said flange.

9. An outlet for the discharge of air from a humidifying duct, said outlet comprising a sleeve mounted in an opening inthe side wall of said duct and extending laterally therefrom, said sleeve having a relatively long internally unobstructed body portion which is tapered toward the discharge end thereof, a relatively short flange extending forwardly and outwardly from adjacent the discharge end of said body portion, a rearwardly and outwardly flaring flange at the inlet end of said body portion adapted to engage the inner wall of the duct around said opening and clips secured to said last named iiange and adapted to be bent over the edge of the wall of the duct surrounding said opening to secure the outlet in said opening.

AGNEW H. BAHNSON, JR.

6 REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 202,501 Woolsey Apr. 16,v 1878 588,643 Hoffman Aug. 24, 1897 690,629 Barber Jan. 7, 1902 946,911 Andrews Jan. 18, 1910 992,081 Tait May 9, 1911 1,224,560 Needham et al May 1, 1917 1,330,920 Stacey, Jr Feb. 17, 1920 1,441,425 Jackson Jan. 9, 1923 1,831,586 Barr Nov. 10, 1931 1,917,299 Hankins July 11, 1933 2,275,572 Somers Mar. 10, 1942 2,332,762 Stempel et al Oct. 26, 1943 2,345,938 Kurth et al Apr. 4, 1944 2,358,847 Bahnson, Jr Sept. 26, 1944 

